Work on the role of disulfide and thiol groups in the functions of axonal membranes is to be continued. The synthesis of optically active, conformationally defined thiol reagents is being pursued, as is the synthesis of group-specific, optically active fluorescent reagents. Studies of the rotational barriers of acetylcholine and of local anesthetics are being expanded. Research attempting to correlate the properties of receptor- proteins isolated from axonal membranes with those of receptor proteins isolated from synaptic membranes has been initiated.